Non-slash weaving



2,797,709 Patented July 2, 1957 NON-SLASH WEAVING Rene Bouvet, Drexel Hill, Pa., assignor to American Viscose Corporation, Philadelphia, Pa., a corporation of Delaware No Drawing. Application February 3, 1954, Serial No. 408,021

12 Claims. (Cl. 139-1) This invention relates to the manufacture of woven textile fabrics and more particularly to weaving without slashmg.

The object of this invention is to provide a method of manufacturing a woven fabric from a continuous filament yarn Without slashing or imparting a high twist to the yarn.

In the art of weaving continuous filament yarn in a warp, the purpose of slashing, i. e., applying a size to the warp prior to Weaving by immersing it under controlled conditions in a sizing solution, is not primarily to increase strength but to hold together the individual filaments of the yarn and thereby present a united and single front against the stress and abrasive action of the loom. This purpose may also be effected by imparting a high twist to the yarn. Twisting overcomes some of the disadvantages of slashing such as the necessity to remove the sizing after weaving; however, to give the yarn a high twist is, in general, less economical than slashing and also requires an additional step in preparing the warp. Heretofore, it has been considered impossible, but it has now been found that a low-twist continuous filament yarn can be woven as a warp on an automatic power loom without slashing if the yarn is made up of individual filaments of relatively large cross-sectional area.

The adjective no-slash as used herein describes a yarn which can be successfully woven as a warp in an auto-- matic power loom without being slashed.

It has also been discovered that for a yarn of a given size, a quantative measure of the ability to withstand the action of a loom is the product of (The number of turns per unit length) X (the cross sectional area of an individual filament) Therefore, to construct a low-twisted no-slash yarn that can be woven with the same eificiency as a highly twisted yarn, the denier of the filaments is increased so that the product of the above factors for the low-twist yarn is the same as that for the high-twist yarn.

Another factor which affects the weaving efficiency of a no-slash yarn is the size of the yarn, i. e., the sum of the cross-sectional areas of the several filaments. Where the size of the individual filaments is constant, the relationship between twist and yarn size with respect to noslash effectiveness is (Turns per unit length) (total cross-sectional area of the filaments) Combining the above relationship with the product of the twist and filament size factors, the following equation for no-slash continuous filament warp yarn is established:

Weaving efficiency: (yarn size) X (cross-sectional area of an individual filament) X (turns per unit length) Since the cross-sectional area of a filament is directly proportional to denier of the filament density denier may be substituted in the efficiency equation for comparing yarns made from the same materials and the equation read E= (yarn denier) (filament denier)' (T. P. I.)

wherein E is weaving efficiency andT/P. I. is the abbreviation for turns per inch- To compare yarns of different materials E is multiplied by l 3 (density) where a significant difference in density occurs. Specific gravity may be substituted for density as a practical expedient. I

To simplify the above formula the obvious substitution of (The number of filaments) (filament denier) for (yarn denier) may be made. The formula is then E=n(filament denier) (T. P. I.)

wherein n is the number of filaments which make up the yarn.

The above set forth formulas are useful in calculating the warp weaving efficiency of no-slash continuous filament yarn of at least 50 denier. There is no upper limit on yarn denier for constructing a no-slash yarn in accordance with this invention and the only practical limit is governed by the particular power loom and its accessories. Yarns from 50 to about 1200 denier can be woven on the looms contemplated by this invention.

It should be noted that formulas described herein apply in general to all continuous filament yarn constructions of at least 50 denier including the highly twisted yarns which are well known in the art. The novelty of this invention, however lies in a method of weaving lowtwist yarn-s. Yarns having ten or less turns per inch and preferably seven or less are contemplated. A twist of ten turns per inch or less is especially advantageous because it can be readily imparted to the yarn in conjunction with the filament forming process as the several filaments are twisted together to form a yarn. A higher twist may be imparted at that time but the rate of filament-forming must be substantially decreased to allow the yarn to be highly twisted as it is collected by conventional means, e. g., a centrifugal bucket employed in the viscose rayon spinning process. The minimum amount of twist is that required to form a yarn which can be handled on conventional textile equipment and is of the order of one half turn per inch. A yam having at least two turns per inch is preferred.

It is obvious from the prior art that a single filament of heavy denier, i. c., about denier, can probably be woven without slashing. It also follows that a yarn comprising more than one such heavy denier filament will withstand the stress of e. loom, but it is an unobvious and wholly unexpected result that a warp yarn composed of three or more continuous filaments of from about eight to fifty denier can be effectively woven without being slashed or highly twisted.

When

E: (yarn denier) (filament denier) (T. P. I.)'*

the acceptable values of E for regenerated cellulose continuous filament no-slas warp yarn are from 2x10 to 7X10 and a value of more than 7X10 is preferred for the most efiicient weaving. If E is multiplied by 1 3 (specific gravity of regenerated cellulose) 4 of no-slas continuous filament regenerated cellulose yarns. On the right are examples of prior art high-twist rayon yarns for which E, calculated as hereinabove described, corresponds to the calculated values of E for the 5 low-twist yarns on the left.

Table I Low-Twist Yarn (Continuous Filament) High-Twist Yarn (Continuous Filament) Observed Weaving Ex. No. Yarn Filament T. P. I. E Ea Yarn Filament T. P. I. E Ea Efficiency Denier Denier Denier Denier 600 30 4 14 1o 4.2 600 4.5 9. e 10 2.s 10 600 10 6.5 11x10 1 3.3 10 150 3.75 18 22x10 6. 5x10 Preferred. 150 30 5 8 5x10 2. 5x10 150 20 6.5 11x10 3.3x10 600 20 3.5 36 10 1 1 10 600 10 5 3 e 10 1 1x10 150 30 4 3 5x10 1 0x10 150 3.75 *12 4.0x10 1.2x10 1 Accept- 150 20 5 38x10 1.1 10 able. 150 10 as 2. 7x10 0.s 10

the acceptable range is from 0.6 10' to 2.0 10' and The results in actual practice of the above examples corthe preferred above 2.0 10 (The specific gravity of responded to those predicted by using the formula regenerated ce lu ose is about 1.5.) The above values taking into account the density factor are defined as Ed E=(yam demer) (filament demer)2(T' D4 and thus as described above. The tests were carried out on a 3 Crompton Knowles S-6 loom as well as on an XK and E a: XD Draper. In all tests the loom was operated at from speclfie gravity 100 to 200 R. P. M. and with standard accessories for continuous filament yarn. Different types of yarn were Values for Ed, therefore, can be applied to continuous used as wefts including rayon, wool, and hair with no filament yarns comprising materials such as polyamides observed difierence in the efficiency with which a fabric including nylon, polyesters including polymers of the eswas woven. ter of ethylene glycol and terephthalic acid, acrylic poly- In addition to the advantages of a low-twist no-slash mers including those containing at least 75% by weight warp yarn stated hereinabove, a fabric woven by the of acrylonitrile, vinyl and vinylidene polymers including method of this invention from viscose rayon warp yarn polyvinyl chloride, polyvinyl acetate and polyvinylidene made up of filaments of from eight to fifty denier shows chloride, polyethylene, protein including corn zein, soya unusual warp dimensional stability to laundering. These bean protein and casein and cellulose esters including acefabrics also unexpectedly respond to the sanforizing tate and butyrate. process. This dimensional stability is attributable at least It is, of course, also necessary when filaments compris- 40 in part to the fact that no strain is introduced into the ing materials other than regenerated cellulose are used to yar'n by swelling and stretching the warp yarns in the construct yarns in accordance with this invention that cerslashing process. As an example of this stability, a fabtain physical properties of the filaments must approximate ric was woven from a continuous filament viscose rayon or be made to approximate the properties of regenerated warp yarn of 600 denier (4.5 T. P. I.) made up of 20 decellulose. These properties include stiffness which should nier filaments without slashing the same yarn as weft. be from about 5 to grams per denier or modified by After five washings in hot (140 F.) soapy water in a rea suitable plasticizer to fall within this range. The surlaxed condition, the fabric shrunk less than 2% warpwise face characteristics of the yarn must approach the smoothand stretched less than 1% in the weft. ness and hardness of regenerated cellulose or a suitable Another advantage of the new method of weaving definish pp to the Y t0 S0 modify its Suffaee- 50 scribed herein is that the weaving efliciency of the warp Strength, which is usually defined in terms of tenacity, yarn can be improved by immersing the cake or cone of elongation, and elastic recovery is not a particularly critiyarn in a sizing solution. The cake-sizing of a warp yarn cal factor in no-slash weaving since a continuous filahaving relatively small filaments is not effective protecment yarn which has sufiicient strength to be wound, spun tion against the loom although the yarn is not stretched and subjected to the usual textile operations prior to weavas it is swollen. With yarns which almost meet the reing has the strength to be woven as a no-slas warp quirements of construction in this invention, however as yarn. This is illustrated by the fact that a highly twisted well as yarns which on the average meet the standards but cellulose acetate yarn whose filaments are relatively low have numerous defects, the cake-sizing process which in strength having a tenacity of about 1.3 grams per dedoes not strain the yarn may be effectively employed. nier, is a very desirable no-slash warp. It is to be understood that changes and variations may Continuous filament yarns comprising essentially the be made in the aforegoing examples and illustrations withfollewillg materials Were modified with respect the out departing from the spirit and scope of the invention above described properties and woven as low-twist noas d fi d i th appended claims, slas warp: nylon (polyhexamethylenedipamide), poly- I claim; vinylchl ri Polyvinylidene Chloride, p y ylonitrile, 1. A method of manufacturing a woven fabric which and cellulose acetate. comprises weaving an unsized continuous filament yarn It is contemplated that in the method of this invention as a arp on an automatic power loom, said yarn having th l p Y be Woven on an automatic power a value of at least 0.6 10" for Ed which is determined loom with standard accessories for weaving continuous by h fo mula filament warp yarns, The looms are operated at the same 1 3 rates of speed as those at which looms in commercial spe0ific gravity) ggg fi T i fi f ggg g gj gi 3 3:; 222 11 5: wherein E is calculated according to the equation. vention. E: (yarn denier) (filament denier) The following table sets forth a number of examples (turns per inch) the yarn having a denier of at least 50, a twist of from one half to 10 turns per inch and made up of at least three filaments of from 8 to 50 denier.

2. The method of claim 1 wherein the continuous filament yarn comprises regenerated cellulose.

3. The method of claim 1, wherein the continuous filament yarn comprises nylon.

4. The method of claim 1, wherein the continuous filament yarn comprises polyvinylidenechloride.

5. The method of claim 1, wherein the continuous filament yarn comprises polyacrylonitrile.

6. The method of claim 1, wherein the continuous filament yarn comprises cellulose acetate.

7. A method of manufacturing a woven fabric which comprises Weaving an unsized continuous filament yarn as a Warp on an automatic power loom operated at from about 100 to 200 R. P. M., said yarn having a value of at least 2.0 10 for Ed which is determined according to the formula 1 3 (specific gravity) wherein E is calculated according to the equation.

E: (yarn denier) X (filament denier) (turns per inch) the yarn having a denier of at least 50, a twist of from 2 to 7 turns per inch and made up of at least three filaments of from 8 to 50 denier.

8. The method of claim 7, wherein the continuous filament yarn comprises regenerated cellulose.

9. The method of claim 7, wherein the continuous filament yarn comprises nylon.

10. The method of claim 7, wherein the continuous filament yarn comprises polyvinylidenechloride.

11. The method of claim 7, wherein the continuous fila ment yarn comprises polyacrylonitrile.

12. The method of claim 7, wherein the continuous filament yarn comprises cellulose acetate.

References Cited in the file of this patent UNITED STATES PATENTS 2,089,191 Dreyfus Aug. 10, 1937 2,169,270 McNally Aug. 15, 1939 FOREIGN PATENTS 295,054 Great Britain Nov. 4, 1929 647,224 Great Britain Dec. 6, 1950 

